The present invention relates to a link information management method for use with an apparatus or a system (e.g. geographical information system) which handles area information (geographical information, document, drawings, etc.) and attribute information (information stored in database or file, etc.).
Geographical information systems have hitherto been known as a system for supporting data retrieval/reference by using a corresponding relationship between geographical information and attribute information. The geographical information system has a fundamental function to retrieve attribute information such as geographical information and residents information from each other. For example, the geographical information system is able to display residents information by designating a house on a map. Conversely, the geographical information system is able to display a house of a corresponding resident on a map by designating a name of resident in residents information. As the geographical system having the above-mentioned functions, there has hitherto been known a self-governing body geographical system xe2x80x9cARISTOWNxe2x80x9d (PIXEL, No. 56, pp. 73-78) having a function to make use of maps and attribute information such as road information and land information in association with each other.
To realize the fundamental function of the geographical information system, a correspondence relationship (hereinafter referred to as xe2x80x9clink informationxe2x80x9d) between geographical information and attribute information should be saved in any forms. Therefore, when the operation of the geographical information system is started, a registration work for registering link information is indispensable for the operation of the geographical information system. Further, during the geographical information system is operated, a maintenance for each of geographical information, attribute information and link information becomes necessary. In a link information registration processing or a link information maintenance processing, since link information is registered and changed while a corresponding relationship between geographical information and attribute information is constantly maintained, the link information registration on processing and the link information maintenance processing become cumbersome as compared with the case where geographical information and attribute information are each registered and changed. Moreover, as the scale and the kind of geographical information and attribute information to be handed increase, the record number of registered link information increases in a combinatorial mathematics fashion. For the above-mentioned reason, there are required many steps of link information registration and maintenance work. To solve this problem, there has been considered a support technology in order to decrease the number of steps of the link information registration and maintenance work.
For example, as a support technology for supporting a link information registration, U.S. Pat. No. 5,625,771 describes a character cursor function. According to the character cursor function, when geographical information and attribute information are associated with each other, an amount of an operator eye movement of on a display screen can be decreased and an efficiency of a link information registration processing can be increased by displaying a part of attribute information near a mouse cursor.
Also, as a technology for supporting a link information maintenance, there is a technology (JP-A-7-73297) for automatically maintaining names of residents on maps by using link information between residents information and geographical information. According to this technology, when a resident of a certain house is changed from the state that geographical information and residents information with respect to the above-mentioned house are linked, for example, a written name of a resident contained in geographical information to which changed resident information should be linked can be changed automatically.
Further, as another technology for supporting a link information maintenance, there has hitherto been known a technology (JP-A-6-28438) for executing a link maintenance between an old map and a new map by correcting position information of link information corresponding to a closed area on the old map. According to the above-mentioned technology, when link information of the old map and the new map in which position information is slightly changed with respect to the old map is corrected (e.g. a map of 1996 edition is changed to a map of 1997 edition), position information which was included in link information of the old map is corrected and then copied to the new map.
As described above, when the geographical information system is operated, there is examined a technology for supporting an access and maintenance of link information.
On the other hand, the above-mentioned conventional technologies are not satisfactory in supporting the access and maintenance of link information. For example, the above-mentioned character cursor function is unable to support the case where there exists link information that has already been registered. That is, when geographical information is updated under the situation that link information has been already registered on geographical-information, the character cursor function is able to only display attribute information obtained before the link information is registered near a cursor. Therefore, link information with respect to current geographical information has to be re-registered one more time from the beginning. That is, the link information that has already been registered cannot be used effectively.
JP-A-7-73297 describes a technology for updating geographical information and residents information when there already existed link information. However, this technology has no support function to support the case where residents information is registered additionally after the link information has been registered. Considering this technology from a system operation standpoint, when new residents information is additionally registered after link information has been registered, it is frequently observed that there occurs residents information which is not corresponding to geographical information (i.e. there exists no link information). However, according to the method described in JP-A-7-73297, the residents information that is additionally registered after the link information has been registered is missed, and hence the residents information that was additionally registered cannot be supported by the link maintenance processing.
Also, JP-A-6-28438 is unable to maintain link information when a scale or a direction is different between old and current geographical information. On the other hand, considering this technology from a system operation standpoint, a class of geographical information that is made corresponding to attribute information also should be changed as business contents handled by the geographical information system are changed. Also, since a business becomes complicated, detailed geographical information become necessary so that a map of scale, 1-50,000 should be changed to a map of scale, 25,000. However, according to the method described in JP-A-5-28438, link information is maintained in a manner in which position information of link information registered on the old map is succeeded substantially as it is. Therefore, when scales or directions of old geographical information and current geographical information are considerably different from each other, link information registered on the old geographical information cannot be correctly changed to link information of current geographical information.
Incidentally, JP-A-9-282330 describes a system for supporting a construction of database by associating database and document as a system similar to the geographical information system. Also in the system described in JP-A-9-282330, link information by which database and document are associated with each other should be registered and maintained similarly to the geographical information system. As a result, there arises a problem similar to the above-mentioned problem from a standpoint of the number of steps in the link information registration and maintenance processing similarly to the geographical information system.
It is an object of the present invention to solve the above-mentioned problems encountered with the conventional technologies and to reduce the number of steps in a link maintenance processing in a geographical information system or the like.
In order to attain the above objects of the present invention, according to a first aspect of the invention, there is provided a link information management method using a computer system including a CPU, an input device, a display device and having a storage device storing first area information concerning a first area including a closed area, second area information concerning a second area including a closed area, attribute information correlated with said first area information and old link information indicative of a corresponding relationship between said first area information and said attribute information. Said link information management method comprises the steps of:
a) displaying the first area and the second area in accordance with the first area information and the second area information, respectively, and obtaining position information of corresponding points of a predetermined number indicative of the same positions instructed on the first area and the second area through said input device;
b) obtaining a translation equation for translating the first area information into the second area information by using the position information of corresponding points and judging similarity between the closed area of the first area information and the closed area of the second area information translated based on the translation equation;
c) generating current link information which causes the second area information and the attribute information to be correlated with each other based on the judged results of the similarity and the old link information; and
d) displaying the attribute information and the closed area on the second area on the display device by using the current link information thus generated.
When the aspect of the invention is applied to a geographical information system, for example, the first area information is old geographical information (geographical information in which link information has been already registered), and the second area information is current geographical information (geographical information in which link information has not yet been registered). When a similarity of closed area is judged, a coordinate transformation processing is executed between the old geographical information and the current geographical information based on the corresponding points designated by an operator, and a similarity is judged by comparing closed areas included in the old geographical information and the current geographical information transformed on the basis of the coordinate transform processing. Incidentally, of attribute information, newly-registered attribute information (information having no link information) may be displayed on the display device.
According to a second aspect of the invention, in the first aspect, the old link information and the attribute information are compared and grouped by using registration/update day in the step c) and the current link information is generated based on compared and grouped results obtained by the registration/update day, judged results of the similarity and the old link information in the step d).
According to a third aspect of the invention, in the first or second aspect, current link information is generated so as to have a class indicative of whether or not generated current link information is certain current link information in the step c), attribute information linked by the current link information and the closed area on the second area are displayed in a first mode or a second mode in response to whether or not generated current link information is certain current link information, and a class indicating whether or not corresponding current link information is certain current link information is changed by operating the displayed attribute information and closed area on the second area in a predetermined manner in the step d).
According to a fourth aspect of the invention, in the first or second aspect, a similarity is judged by using character recognized results obtained within closed areas of the closed area of the first area information and the closed area of the second area information in the step b), and current link information is generated by using the character recognized results in the step c).
According to a fifth aspect of the invention, in the first or second aspect, a data format of the first area information and a data format of the second area information are different from each other. For example, even when old geographical information is of the vector format and current geographical information is of the image format, link information can be changed based on respective position information.